So when I create a new routine on this site it tells me to do 20reps, 16reps, 12reps. Why are the rep counts so high? Is it cause i selected to lose weight? And if I follow these rep counts how much weight should I be looking to use? I can Bench 50lbs about 16-18times right now but I’m assuming this is scaling up for weight and down for reps so that 50 would be the last weight I use correct? I’m still a newbie when it comes to this stuff.
I would imagine the rep counts are higher due to you selecting lose weight. Generally speaking if you are looking to lose weight and not bulk up, higher reps is fine. I personally think 20/16/12 is a bit high. I would stick with no more than 12 and do something more like 12/10/8 if you are doing 3 sets. Yes, you should select a weight that you are comfortable lifting with proper form to hit your rep goal while assuring it's not too easy. This can take a little time to learn what weight you should be using.
If you can do 50 16 to 18 times, I would suggest doing 60 or 65 and see if you can do a set of 12 or 10 and what difficulty it is. If it's too easy, try 70 ect. Slowly move up to where the last rep in a 10 rep set is hard but no so hard that you fail.
No need to rush, take time to assure you have good form as well - if you stick with it in the coming weeks/months you will have a routine in, you will have learned your limits and will watch them increase.